LayerRefImpl's 'owner' field seems to be null. !ENTRY org.eclipse.core.runtime 4 2 Oct 04, 2004 19:55:03.843 !MESSAGE An internal error occurred during: "Rendering". !STACK 0 java.lang.NullPointerException at net.refractions.udig.project.internal.LayerRefImpl.getZorder(LayerRefImpl.java:77) at net.refractions.udig.project.internal.LayerImpl.getZOrder(LayerImpl.java:87) at net.refractions.udig.project.render.AbstractRenderer.getOrderPosition(AbstractRenderer.java:141) at net.refractions.udig.project.internal.render.RenderStackImpl$RendererComparator.compare(RenderStackImpl.java:242) at java.util.TreeMap.compare(TreeMap.java:1093) at java.util.TreeMap.put(TreeMap.java:465) at java.util.TreeSet.add(TreeSet.java:210) at net.refractions.udig.project.internal.render.RenderStackImpl.buildJAITree(RenderStackImpl.java:284) at net.refractions.udig.project.internal.render.RenderStackImpl.updateReady(RenderStackImpl.java:132) at net.refractions.udig.project.render.AbstractRenderer.fireUpdateReady(AbstractRenderer.java:227) at net.refractions.udig.project.render.AbstractRenderer$RenderJob.run(AbstractRenderer.java:335) at org.eclipse.core.internal.jobs.Worker.run(Worker.java:66)